Radon exhalation from uranium tailings. Comparison of experimental and theoretical data

Two different experimental methods and a theoretical approach are used to calculate 222Rn fluxes in the soil-atmosphere interface. As a common experimental procedure, an open-faced 30 liters cylindrical container was inverted and placed onto the tailing surface with the open face down. After a 24 h period, to balance any possible disturbance, the interior air was analysed. One of the experimental methods is based on integrated 222Rn measurements of the accumulated air-gas mixture, using solid nuclear track detectors placed inside the container. The other method is based on spot air samples using scintillation cells, being the 222Rn concentration measured in equilibrium. The radon flux theoretical values are estimated from the 226Ra content of the tailings material, determined by gamma spectrometry, and using the diffusion equation. The series of results obtained by the referred methods were compared